1. Technical Field
The present invention relates to projectors, projection systems, and methods for controlling the projection system.
2. Related Art
In recent years, a projector has been used in a presentation for an exhibition, an academic meeting, a conference, etc., or in a home theater. The use of the projector makes it easier to produce a large-screen display as compared to a direct-view-type display device such as a display, and thereby allows more people to view the same image and enhances convenience.
The concurrent use of a plurality of projectors makes it possible to display images side-by-side or display images so as to overlap each other. By using the projectors in the manner as described above, it is possible to obtain a larger and higher-resolution projected image by splitting a horizontally oriented image such as a panoramic photograph into a plurality of images and displaying the images side-by-side by using the projectors. In addition, it is possible to make a presentation while referring to a plurality of pieces of data without screen switching by displaying a plurality of tables or graphs at the same time by using two projectors.
However, when the projectors are used concurrently in the manner as described above, it is necessary to devise a new method of producing good quality image display. For example, when a panoramic photograph is displayed by piecing together a plurality of images, the positioning or color of the adjacent images has to be adjusted so that the joints of the images are not perceived by the observer.
It is for this reason that the ways to attain good display when a plurality of projectors are used concurrently have been proposed (for example, refer to JP-A-2006-229400 (Patent Document 1) and JP-A-2008-151838 (Patent Document 2)).
Patent Document 1 proposes a configuration which easily displays an image in which borders between the display images are not perceived when the images are joined together by using a plurality of projectors while making the edges of the images overlap one another. Specifically, each projector displays a dedicated image for good positioning of the borders of the images and information indicating the number and layout of projectors which are used, and takes images of the image and information displayed by an adjacent projector, thereby allowing a decision to be made about a part of the edge of the image displayed by each projector, the part in which the images overlap each other, and adjusting the luminance of the part where the images overlap each other. In this way, good image display is produced.
Moreover, Patent Document 2 proposes a configuration in which a control apparatus performing overall control of a plurality of projectors controls the luminance and chromaticity of the image projected from each projector in such a way as to prevent the borders generated by the difference in color between the images from being perceived at the border portions between the images when a plurality of images are joined together, and produces good image display.
Incidentally, a projector sometimes has a plurality of operation modes set in advance to make the user produce proper image display according to an image to be displayed or the usage of the projector. The “operation modes” here refer to drive conditions of an image forming apparatus, a lamp, etc. installed in the projector and correction conditions of image data, the drive conditions and correction conditions set in advance to produce image display of intended image quality.
For example, in a “cinema mode” suitable for projecting a movie with good images, the drive conditions and correction conditions are set to make the color, contrast, brightness, etc. of the display images meet the conditions suitable for projecting a movie to make it possible to produce display with a quiet color and deep black display. Moreover, in a “data mode” suitable for displaying data such as a table and a graph, the drive conditions and correction conditions are set to meet the conditions in which emphasis is placed on contrast so as to make letters and lines more visible.
As a result of such “operation modes” having been set in advance, the user is allowed to obtain suitable image display easily.
However, when image display is performed by using a plurality of projectors in the manner as described above, the colors etc. of the projected images lose the unity if the projectors have identical operation modes, making it impossible to produce good image display as a whole.
For example, the recent technical development makes the projector compact and makes it easy to carry the projector around. Therefore, for example, when the projectors are used in different locations in different operation modes and are then brought together in one location, the projectors may have different starting operation modes.
Under such circumstances, when settings are changed individually to change the operation modes of the projectors, it takes time to install the projectors. Moreover, when the operation modes are reflected in each other's operations modes by performing two-way communication between the projectors, it is necessary to connect wires for wire connection and make corresponding projector settings and security settings for wireless connection, making the installation complicated.